Results 1 to 12 of 12

Thread: Wobble at 60mph

  1. #1
    apriliaforum prov-nov
    Join Date
    Aug 2017
    Location
    Napa CA
    Posts
    80

    Wobble at 60mph

    I just brought back a Scabby 200 (2008) from the dead. It had been sitting in a garage for a few years. Put some new fuel in it and it fired up. Itís running good albeit a little bad fuel still in the system but am working it out.
    Problem I am having is from 0-45 this thing runs and rides great. When i get on the highway at about 55+ mph, it gets a little wobbly. I am thinking maybe its the tires as they both donít look the greatest and they were low on air when I get them. Do you think after time the tires could of worn in a flat spot for sitting so long and the flat spots only show up when its high speed?
    2016 Piaggio BV 350
    2008 Yamaha WR 250

  2. #2
    apriliaforum expert
    Join Date
    Apr 2011
    Location
    Clearwater, Fl
    Posts
    7,568
    Tread could be getting ready to separate and is squirming on the casing at higher speeds. Tires in a hot California garage would be suspect after long time storage even if they were never mounted so they should be the first thing to go regardless of how much tread they had left.

    If they have been run under inflated they could also have uneven tread wear from braking which depending on the tread pattern can set up a head shake harmonic at certain speeds as the tread on the left and right alternately makes primary contact with the road. This is more common with the Chevron type tread patterns.

    Here is an example of an alternating Chevron tread (front tire on the left) that would be more prone to developing head shake from under inflation combined with aggressive braking which will cause gaps in the contact patch of the tire as the Chevrons squirm during braking from the inadequate pressure which will cause the leading edge of the Chevron block to wear faster than the trailing edge. Note that sometimes if a rider is particularly aggressive with the front brake he may have to up the tire pressure 1 to 3 psi over whats stated on the tire pressure label mounted on the bike (without going over the max psi stamped on the tire)


  3. #3
    apriliaforum expert armadillored's Avatar
    Join Date
    Aug 2006
    Location
    Cleveland, Ohio, USA (now in Murrells Inlet, SC
    Posts
    1,407
    good call Rockynv
    '67 BMW R69S-"Toots" in rehab
    '09 Silver SC250
    Previous rides:
    '04 Chinese 125
    '06 X9-500
    '08 MP3-400
    '06 BV500

    '09 Mana

  4. #4
    apriliaforum prov-nov
    Join Date
    Aug 2017
    Location
    Napa CA
    Posts
    80
    Much obilged. New tires it is!
    2016 Piaggio BV 350
    2008 Yamaha WR 250

  5. #5
    apriliaforum expert
    Join Date
    Jun 2013
    Location
    croatia
    Posts
    2,304
    yes new tires are often the answer, if you know that the bike was just sitting and wasnt in an accident then tires are the cause of the wobble.
    They deform when they sit for a long time. So chang them, get them balanced and everything should be just fine.

  6. #6
    apriliaforum Junkie
    Join Date
    Jun 2016
    Location
    Florida
    Posts
    331
    16" tires? I would be putting some BT45s or Michelins.

    For giggles...whats the date code on your present tires???

  7. #7
    apriliaforum Junkie
    Join Date
    Jun 2016
    Location
    Florida
    Posts
    331
    Quote Originally Posted by jog View Post
    yes new tires are often the answer, if you know that the bike was just sitting and wasnt in an accident then tires are the cause of the wobble.
    They deform when they sit for a long time. So chang them, get them balanced and everything should be just fine.
    where do you get that? Sitting tires dont deform. Even if under inflated.

    Also it cracks me up that folks are trying to diagnose a wobble issue when they arent within 10' of the bike. Could be a loose axle or bent rotor, missing wheel weights, or a screw embedded in the tire.

  8. #8
    apriliaforum expert
    Join Date
    Jun 2008
    Location
    RDU/ North Carolina 919 914 4029
    Posts
    6,346
    Or many year old dried out tyres..

  9. #9
    apriliaforum expert Southpaw56's Avatar
    Join Date
    Aug 2008
    Location
    Winnipeg, Manitoba, Canada
    Posts
    1,013
    Tires are likely an issue, but I also have a Beo 200 and the front end has always felt a bit wobbly from new. I have had several sets of tires (Michelins now). My thoughts are that the skinny fork legs and how they are mounted as well as the narrow handle bars and of course the road you ride on give that sensation at the speeds you are referring. I think a fork brace may also help somewhat (it did on my other bike) but that may have to be a custom item. I've checked everything on the front end to make sure it's tight and safe so I wobble with confidence.

    Sp56

  10. #10
    apriliaforum expert
    Join Date
    Apr 2011
    Location
    Clearwater, Fl
    Posts
    7,568
    Quote Originally Posted by Southpaw56 View Post
    Tires are likely an issue, but I also have a Beo 200 and the front end has always felt a bit wobbly from new. I have had several sets of tires (Michelins now). My thoughts are that the skinny fork legs and how they are mounted as well as the narrow handle bars and of course the road you ride on give that sensation at the speeds you are referring. I think a fork brace may also help somewhat (it did on my other bike) but that may have to be a custom item. I've checked everything on the front end to make sure it's tight and safe so I wobble with confidence.

    Sp56
    Sometimes having the rear shocks set to soft or worn silent blocks that the engine pivots can also contribute to wobble. Also if you really load up your top case sometime it will require bar end weights to help mute the wobble.

    For a fork brace Space Tiger found some that were designed for the smaller MotoGuzzi motorcycles after a little judicious trimming would work well with the 250cc Aprilia Scooters so there is a possibility there may be one to match the diameter and spacing of the fork tube on the Scarabeo 200.

  11. #11
    apriliaforum prov-nov
    Join Date
    Aug 2017
    Location
    Napa CA
    Posts
    80
    I put new tires on it and we are good to go. My next problem in a new category
    2016 Piaggio BV 350
    2008 Yamaha WR 250

  12. #12
    apriliaforum expert
    Join Date
    Apr 2011
    Location
    Clearwater, Fl
    Posts
    7,568
    Quote Originally Posted by FastCletus View Post
    I put new tires on it and we are good to go. My next problem in a new category
    Great to hear it was the simple solution. Watch the front tire for uneven wear and if need be adjust the tire pressure up a pound or so to cope with it.

Similar Threads

  1. Aprilia Sportcity 125 rear wheel seized whilst driving at 60mph
    By AndrewJMKennedy in forum Aprilia and Piaggio 150cc-350cc
    Replies: 4
    Last Post: 07-20-2016, 09:35 PM
  2. dies at 60mph
    By Roach61 in forum Aprilia and Piaggio 150cc-350cc
    Replies: 8
    Last Post: 03-18-2016, 04:16 PM
  3. Rear Wheel wobbling at high speeds
    By soamz in forum 2010-2019 RSV4 - All Variants
    Replies: 30
    Last Post: 04-25-2014, 07:25 AM
  4. Front end wobble at speeds
    By satkins93 in forum Aprilia and Piaggio 500cc
    Replies: 4
    Last Post: 04-03-2011, 11:04 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •